An LTE-Advance (Long Term Evolved-Advance, long term evolved-advance) network is a communication network on which manufacturers are researching actively, and is an advancement of the LTE network, the objective of which is to provide a low-cost network capable of reducing time delay, improving a user data rate, and increasing system capacity and coverage.
As an advanced technology in the LTE-A, the relay technology may improve a data rate of an edge user and a spectral utilization rate of the system and increase the system capacity and coverage through a method of setting up an RN (Relay Node, relay node) between a UE (User Equipment, user equipment) and an eNB (E-UTRAN NodeB, E-UTRAN NodeB). The eNB communicating with an RN is called D-eNB (Donor eNB, donor eNB). An interface between the UE and the RN is called a Uu interface, and an interface between the RN and the D-eNB is called a Un interface. When the Un interface and the Uu interface share a part of frequency resources, and when downlink data is sent, an MBSFN (Multicast Broadcast Single Frequency Network, multicast broadcast single frequency network sub-frame) is used at the Un interface, and a non-MBMSFN sub-frame is used at the Uu interface.
According to the existing interface protocols, the UE reports an amount of uplink data, required to be transmitted, of the UE by sending a BSR (Buffer Status Report, buffer status report) to the eNB, so as to request the eNB to allocate uplink transmission resources to the UE. The eNB performs grouping on the UE according to a priority level of an RB (Radio Bearer, radio bearer) corresponding to a current service of the UE, and the UE reports to the eNB by group. After the BSR is triggered, if the UE is configured with dedicated SR (Scheduling Request, scheduling request) resources, the UE sends an SR request message to the eNB through the dedicated SR resources, to request the eNB to allocate resources, which are for sending the BSR, to the UE. After the eNB receives the SR request message, uplink transmission grant, which is used by the UE to send a BSR request, is allocated to the UE according to a scheduling result.
Currently, the existing method for BSR reporting is not applicable to the interface between the RN and the D-eNB, and no reasonable method for BSR reporting used between the RN and the D-eNB exists in the prior art either.